MÉRENS-LES-VALS, France – 5:00 a.m. It’s dark at this hour of the morning, and the mist rolling through this convergence of valleys has an unearthly glow against the jutting black peaks of the Pyrenees. We’ve only got two hours to make the 175 km drive from Andorra to the Toulouse Airport, and the empty road is a pale, silvery strip that loops and folds back upon itself on its gradual descent of the mountain.

Ten kilometres of hairpins and switchbacks lay before me, and my world is reduced to the heavy suede wheel in my grip, the decisive bite of the carbon-ceramic stoppers, and the booming downshifts echoing off the rock walls. One miscalculated apex or understeer-induced slide, and it’s an arse over teakettle cartwheel – 6,000 feet to the bottom.

According to the old adage, “There’s no replacement for displacement,” but the RS 5’s superb sense of balance is at least partly due to its outgoing V8 being supplanted by a new bi-turbo V6. There’s no reduction in power – the new engine matches the 450 hp output of the larger eight-cylinder – and actually bumps up the torque from 317 to 443 lb-ft. The lighter mill gives the car a better front-to-rear weight ratio, shedding some 68 lb in the transition.

But the rest of the credit surely belongs to its new MLB Evo architecture, a high-strength steel and aluminum platform that’s 132 lb lighter than its predecessor and imbues the RS 5 with an immutable feeling of stability. The old trapezoidal-link rear suspension has been replaced with a new five-link setup, with another updated five-link in front delivering sharper turn-in and handling.

Although Audi claims the RS 5’s new design is inspired by the 1980’s Audi 90 Quattro, we’re hard-pressed to see the resemblance. The new car is sleek, with knife-sharp creases in its aluminum skin. The muscular arches are some 15 mm wider than the more pedestrian A5/S5 coupe, with front venting and rear diffusers adding visual punch to the fascia. All RS 5s come with black trim, and 20-inch forged alloy wheels, and the Dynamic Pack adds red brake calipers and a black-tipped sport exhaust. Our tester boasts a carbon-fibre roof panel whose lacquered weave not only looks slick, but shaves off another centre-of-gravity-improving 3 kg of weight. This Europe-only option is unfortunately not available for North American cars.

The cabin is typical of Audi: beautifully rendered in top-notch materials, with just enough race-inspired design cues to hint at the RS 5’s sportiness, but never crosses the line into boy-racer garishness.

Highly bolstered sports seats are upholstered in top-grain leather and quilted Alcantara with contrasting red stitching – which is repeated on dash and door panels. Since 90 percent of the previous RS 5’s buyers opted for carbon-fibre trim, it’s now standard on all North American-spec cars. The extra 7.3 cm in length increases rear leg room by 2.5 cm – still, it’s not exactly accommodating for adult-size passengers.

In true sports-car style, the cockpit is bisected by a horizontal bank of switchgear, and there’s a fat and grippy flat-bottomed wheel. Audi’s Virtual Cockpit is a benchmark of digital instrumentation, providing a configurable display of navigation, speed, fuel consumption and other relevant information. New for this year, is an RS-only head-up display showing speed, nav, lap times and gear shift info. It’s a beautiful environment: the sports seats grip like a velvet glove during even the most fierce cornering, yet remain road-trip comfortable. Not a thump, rattle, nor squeak enters the whisper-quiet cabin; in fact, we have to lower the window to enjoy the crackling exhaust burble on our way through the tunnels.

Speaking of which, there’s no denying that the bi-turbo V6’s sounds weak compared to the bellow of the naturally aspirated 4.2-litre V8. Switch into Dynamic Mode, and there’s a lovely warble on downshift, but it’s a product of unspent fuel from an additional injector exiting the optional sports exhaust.

The V8 produced an inimitable rumble, its basso profondo bark distinguishing the previous RS 5 as a German muscle car. But the V6’s impressive torque, available from 1,900 to 5,000 rpm quickly dispels any disappointment one feels over the retired V8, with its instant, ferocious power. And the Gatling gun–performance of the new ZF eight-speed automatic is heady compensation for the outgoing dual-clutch automatic.

The RS 5 is available with Dynamic Ride Control suspension consisting of steel springs and three-stage adaptable shocks. Our tester came equipped with the optional Dynamic Plus pack, featuring enormous 15.7-inch carbon-ceramic brakes, carbon-fibre engine trim and a speed governor bump from 250 to 280 km/h. Audi claims the new car can sprint from zero to 100 km/h in 3.9 seconds. Power is channelled through all four wheels, with the rear sport differential actively dividing the torque and applying individual braking to all the wheels for enhanced cornering ability.

It all adds up to a car that’s deceptively fast on a twisty course. The tight chassis and terrific damping allow the car to be pushed hard into the corners, and the optional carbon ceramic brakes are astonishing. With no rebound to recover from, the car remains stable after braking, and the driver can get back on the gas quickly. Yet there’s little drama to the RS 5’s demeanour: it can be driven hard over a challenging course, then immediately settles down to its job as a refined grand tourer. Switch the adaptive suspension to Comfort and it’s as creamy-smooth as any soft boulevard cruiser. Indeed, once we’d dispensed of the mountain and its spaghetti-like curves, we coursed along the motorway in serene comfort and eventually reached our destination with minutes to spare.

While there are no prices available yet, we expect the RS 5 to start around $90,000 and increase accordingly with options. It should arrive in Canadian showrooms in the first quarter of 2018.